use strict;
use warnings;
use IPC::Shareable;

my $scalar;
my $foo = tie $scalar, 'IPC::Shareable', 'k123',
              { create => 1, destroy => 1 };

my $pid = fork();

if(! defined $pid) {
    die "fork err";
} elsif($pid == 0) {
    # Child
    undef $foo;
    untie $scalar;
    print "Child ends\n";
    exit 0;
} else {
    # Parent
    sleep(1);
    undef $foo;
    untie $scalar;
    print "Parent ends\n";
}